The procedure generally adopted at the present time for the transport of money between companies and banks, for example, is for bank notes and possibly coins to be placed inside cassettes, i.e. inside metal containers with lids which are then locked. Both the sender and the recipient hold keys for the cassettes in question, of course. In order to increase security during transport and holding, it has previously been suggested that the cassettes should be equipped with locking devices such that they are locked with one key and are unlocked with a different key. What this means in practice is that the company has one key for locking the cassette, and the bank or some other recipient has another key for unlocking the cassette, or vice versa. The underlying idea for the system is attractive, although it is not considered to provide adequate security to meet current and furture safety requirements.
The present invention is based on the aforementioned underlying idea with two separate measures for the locking and unlocking functions. The invention is intended first and foremost to be applied in conjunction with computer equipment, whereby considerable security is achieved and tampering with the locking function is prevented. There is also a requirement to prevent unauthorized access to the contents which are to be transported or stored.